Seattle Fire
Department
Infectious Disease
Monitoring Update

1/13/2014
Comments: As reported
over the past two weeks, widespread influenza activity is occurring in most of
the Unit States, including Washington and King County. A substantial increase in
confirmed influenza viruses through the end of December has detected by the UW
Virology Laboratory and reports to King County Public Health also show
substantial increases through the end of December. However the 14-day moving
average of influenza-like symptoms reported through the Infectious Disease
Monitoring program peaked the first week of January and has leveled off.
It will be interesting to see if influenza and other virus activity as confirmed
by UW Virology and King County Public Health also show a leveling off.

1/13/4/2013
Comments: The percentage of patients with influenza-like symptoms (ILS)
peaked in mid-February and has dropped fairly consistently since then. The
level of (ILS) is back to "normal" for this time of year, consistent with
previous years. This is also consistent with the significant drop in confirmed
virus cases from the UW Virology Lab from February 9th through the 16th.

1/28/2013
Comments: A significant increase in influenza-like symptoms (ILS)
has occurred over the past two weeks. Data and charts (link above) show
that the percentage of patients seen with ILS is now
comparable to the second wave of the 2009 H1N1 pandemic outbreak. The
Coefficient of Determination for a 14-day moving averages (from the data page)
are above 0.9 for ILS, fever and fever with other symptoms, and the fever or
cough or respiratory. The raw number of patients with ILS has increased
30% in the past two weeks. Also, the geographic distribution of patients
with ILS indicates that flu-like symptoms are fairly wide spread around the
city. Two maps - generated from the First Watch monitoring and alerting
system - for ILS events January 1 through January 27, 2013 show the distribution
of Fever and the
Cough-Fever-Respiratory
combination of symptoms.

1/18/2013
Comments: As
widely reported, influenza is prevalent in
the region and is reflected in the number and percentage of patients with
influenza-like symptoms. The charts (accessible from the link above) show
a substantial increase in symptoms over the past couple of weeks. The
Coefficient of Determination for a 7-day moving average from December 7th to now
is 0.8 for fever and fever with other symptoms, and 0.9 for cough, fever,
respiratory and other symptoms.

1/2/2013
Comments:Consistent
with previous years, influenza-like symptoms found in the field have
significantly increased from mid-December to now. The significance of the
increase is reflected in the Coefficient of Determination: 0.83 for ILS
overall, 0.6 for fever and fever with other symptoms, and 0.84 for fever or
cough or respiratory. (A score of 0.7 or more is a significant increase
and less than 0.4 is an insignificant change.)

The King County Public Health and UW Virology Lab are now reporting significant
increases in influenza-like illnesses and laboratory confirmed influenza viral
strains from 12/1/2012 through 12/22/2012.

12/15/2012
Comments: Influenza-like symptoms
found in the field have tapered off from early December to now. This is consistent with prior years. However,
King County Public Health reported increases in confirmed influenza through
12/8/2012 from prior weeks. Additional scrutiny of the Fire Infectious Disease
Monitoring Program data and Public Health data will be done over the next 2
weeks to determine if the symptom trend is consistent with the confirmed cases
of influenza and similar viruses. FYI:
the ProMed web site has reported multiple cases of rat bite fever in Chelan and
Douglas counties and possibly Grant county. Symptoms are similar (but not
identical to influenza.) Read the notice
here.

12/03/2012
Comments: As
reported by ProMED (http://www.promedmail.org/) this past week there has been
a significant increase in flu activity in the south-central and southeast of the
country. Virus activity tracked by King County Public Health indicate an
increase in certain illnesses but nothing significant.
The percentage of patients with symptoms tracked by the Fire Department has
been relatively flat through November and is generally consistent with prior flu
seasons.

10/20/2012
Comments: Over
The percentage of patients with ILS has steadily increased
over symptoms found in October. The increase is generally
consistent with the increase in Rhinovirus and Parainfluenza viruses detected by the UW Virology
Laboratory and reported by King County Public Health. The increase in
November is consistent with
the increase for the same time period during the 2011-2012 flu season.

10/20/2012
Comments: Over
the past few weeks the percentage of patients with ILS has increased
over symptoms found in September. The increase is generally
consistent with increase in Rhinovirus and Parainfluenza viruses detected by the UW Virology
Laboratory. The increase in October is also consistent with
increase in ILS at the start of the 2011-2012 flu season.12/19/2011
Comments: Over
the past 10 weeks the percentage of patients with ILS has been
relatively flat with up-and-down flucuations. ILS increased in October
through mid November, dropped from mid-November to early December and
have increased in the past two weeks. The pattern is generally
consistent with confirmed cases of viruses detected by the UW Virology
Laboratory.

10/01/2011
Comments: Influenza-like
symptoms (ILS) have been relatively flat since the end of the
2010-2011 flu season (end of April). This is consistent with
the confirmed cases of viruses detected by the UW Virology Laboratory.
If symptoms found in the field start to increase in the first two weeks
of October it will be consistent with prior year's trends, and
consistent with the start of a new flu season.

02/10/2011
Comments: Influenza-like
symptoms (ILS) have increased from mid-January through the first week
of February. As reported by King County Public Health and UW
Virology Laboratory there has been an increase in Influenza A and other
viruses (Respiratory Syncytial Virus, Rhinovirus) from mid-January to
the end of January. The pattern of increase (Dec-Jan) - decrease
(Jan) - increase (Jan-Feb) in flu symptoms found is consistent with the
past two years. Also, the pattern of flu symptoms found is tracking
fairly closely with confirmed viruses - i. e., but about 1 week ahead of
laboratory confirmed cases.

01/17/2011
Comments: Influenza-like
symptoms (ILS) have increased from mid-December through the first week
of January but have started to decline. This is consistent with
increase/decline in 2007-thru-2009 period. In other words,
the fluctuation is normal for this time of year.

12/30/2010
Comments: Influenza-like
symptoms (ILS) have increased over the past two weeks but the increase
is consistent with increases in 2007-thru-2009 period. In other words,
the increase is normal for this time of year. The
14-day moving averages have correlation coefficients ranging from 0.86 to 0.93
(and associated R-squared values of 0.78 to 0.87).

11/22/2010
Comments: Influenza-like
symptoms (ILS) have increased significantly over the past two weeks. The
14-day moving averages have correlation coefficients ranging from 0.95 to 0.97
(and associated R-squared values of 0.90 to 0.94). See the Data & Charts
link below.

Data from the first two weeks of November from
King County Public Health and UW Virology have not shown an increase in
confirmed influenza or influenza-like-illness. The Fire Department symptom
data will be monitored more closely over the next two weeks to see if the
pattern continuous.

10/25/2010
Comments: Influenza-like
symptoms (ILS) followed a pattern in September and October similar to
previous years - i. e., an increase in late August through mid
September, a decrease in mid-September to late October.
Influenza-like symptoms have increased over the past two weeks. The
14-day moving averages have statistically significant correlation
coefficients ranging from 0.68 to 0.95 (and associated R-squared values
of 0.475 to 0.91).

The increase may be the result of an increase of
Repirsatory Syncytial Virus (RSV). RSV is not an influenza virus but one that is
common in the community and associated with the "common cold". The UW Virology
Laboratory reports of confirmed RSV cases shows a significant increase from
September 18 and October 16, 2010 (correlation coefficient of 0.88) and greater
increase between September 25th and October 16th (correlation coefficient of
0.94).

08/22/2010
Comments: Influenza-like
symptoms are increasing and starting to mirror the start of the
2008-2009 normal flu season. The 14-day moving averages have
statistically significant correlation coefficients ranging from 0.80 to
0.85 (and associated R-squared values of 0.65 to 0.73).

05/30/2010
Comments: Influenza-like
symptoms have returned to normal seasonal levels. There was a
minor outbreak of Norovirus in April which may explain the increase in
symptoms found during the first two weeks of that month. The rate
of ILS
has dropped back to expected levels and are slightly below the level of
symptoms found in the 2007 and 2008 for the April-May time period.

An updated report on the monitoring program that was presented to
Fire Department paramedic management and staff in December 2009 is
contained in the Analytical Reportssection.
In addition, a short report on the value of using responses to
dispatcher medical questions in detecting flu-like symptoms is
accessible from the Analytical Reports page.

02/27/2010
Comments: A
substantial decrease in influenza-like
symptoms (ILS) has occurred in the past two weeks and ILS levels are
well below levels observed in 2007 and 2008 for this time period.
The previous increases in early February may have
been due to an
increase in illness from non-influenza viruses. The UW Virology labs noted a significant increase
in
Respiratory Syncytial Virus (RSV) from late November 2009 through to
February 13, 2010 while detected influenza viruses remained
constant-to-declining for this time period.

02/13/2010
Comments: Influenza-like
symptoms (ILS) continue to increase over the past three weeks consistent
with increases during this time period in 2007 and 2008. Coefficients of
determination (R-squared) for symptom categories
range from 0.8 1to 0.95. Go to the Data & Charts
link, below for details.

02/9/2010
Comments: Influenza-like
symptoms (ILS) have substantially increased over the past two weeks and
have reached the same levels observed in 2007 and 2008 for the same time
periods. Coefficients of determination (R-squared) for symptom categories
range from 0.89 to 0.91

02/2/2010
Comments: The occurrences of
influenza-like symptoms (ILS) over the past two weeks have started to
increase consistent with increases in the same time period in 2007 and 2008.

01/18/2010
Comments: The occurrences of
influenza-like symptoms (ILS) over the past two weeks have dropped
slightly below the same time period in 2007 and 2008. The trend has been down (i. e., R-squared values
are pointing in the negative direction).

01/11/2010
Comments: The occurrences of
influenza-like symptoms (ILS) have leveled off over the past two
weeks.
At this point the percentage of patients with symptoms are slightly below
the same time period in 2007 and 2008.

01/02/2010
Comments: The occurrences of
influenza-like symptoms (ILS) continue to increase over the past two
weeks. Coefficients of determination for the moving average values between 12/19 and 01/01/2010
are 0.5 to 0.9 (a significant increase from zero for the 12/13-12/26
period). The increase is consistent with the increases observed in
the same time period in 2007 and 2008.

12/27/2009
Comments: The occurrences of
influenza-like symptoms (ILS) are starting to increase. This is consistent with trends during the 2008 and 2007 flu seasons
- i. e., from mid-December to the end of December the occurrence of ILS
starts increasing. Correlation
coefficients for the moving average values between 12/13 and 12/26/2009
are zero. Since the previous trend was negative (declining) the
fact that the coefficients are now zero indicates a reversal of the
downward trend. See Data and
Charts link, below.

12/19/2009
Comments: Symptoms found are
now slightly below levels observed in the 2008 flu
season and equivalent to the 2007 flu season. Correlation
coefficients for the moving average values between 12/6 and 12/19/2009
are significant and negative (-0.97) indicating a steep drop in symptoms
found amongst patients during this time period. See Data and
Charts link, below.

12/04/2009
Comments: Symptoms found are
now at the levels observed in the 2007 and 2008 flu
periods. See information on the Data and Charts link below.

12/04/2009
Comments: Continued drop in the percentage of
influenza-like
symptoms (ILS) found from the previous 14 day period. Symptoms found are
now very close to the levels observed in the 2007 and 2008 flu
periods.

11/29/2009
Comments: The percentage of
influenza-like
symptoms (ILS) found has dropped in the past 14 days below the levels that occurred during the April H1N1 outbreak and are
starting to return to the levels observed in the 2007 and 2008 flu
periods.

11/16/2009
Comments: The percentage of
influenza-like
symptoms (ILS) found has flattened out over the past 14 days and remain
at the same (peak) levels that occurred during the April H1N1 outbreak. The
R values for the
different flu symptom tables range essentially "zero".

11/10/2009
Comments: The percentage of
influenza-like
symptoms (ILS) found has declined in the past 14 days and have returned
to the same (peak) levels that occurred during the April H1N1 outbreak. The
R values for the
different flu symptom tables range from 0.59 to 0.85 in the negative
(declining) direction.

11/04/2009
Comments: The previous 7 days
shows a leveling off in the percentage of patients with influenza-like
symptoms. The percentages remain significantly above those found
during the H1N1 outbreak earlier this year and significantly above the
percentages in the previous two years.

10/30/2009 Comments:
The previous 14 days indicate a steady increase in the percentage of
patients with influenza-like systems (ILS). The link below lists
data for the previous 14 days. The growth in symptoms is measured
by the coefficient of determination (R).
The closer to 1 the R value the stronger
the increase is over the 14 day time period. The R
values for the different flu symptom tables range from 0.88 to 0.95.
This indicates very significant growth.